Art of grinding



Feb. l5, 1944. G. D. 'SCHOGER 2,341,820

ART oF GRINDING Filed July 20, '1943 Ummm,

Patented Feb. 15, 1944 UNITED STATES PATENT lOFFICE ART F GRNDKINGGeorge D; Schoger, Anderson; Ind." Application July .20",` 1943, SerialNo. 195;485

(Cl. 125-l1`) l@ Claims;

This invention relates to the art of grinding.

The invention is designed more,particularlyforV use in connection withgrinders in which the work is carried on-a bed ycapable oi reciprocationandwhich is provided with suitablev headstock and tail stock formationsthe centers-cf whichv serve to xedly. position the Work relative-to thegrinding face. commercial service, and it is apparent that asta resultci such service the-grinding face or faces require dressing at intervalsin the form oi.

sharpening or truing, the grinding faces -by the use of a tool orimplement `which includes a dressing agency-generally a diamond- Which vis caused to traverse the curved'faceof thegrinding Wheelas *thev latteris rotated.V The `toolis positioned at the mosteicient angle for serv--ice, and must be xedly held in its adjustedposition during the truingoperationwhile traversing the face of the Wheel through the movementofthe bed. Where it is `necessaryfto adjust: the i tool each-time it isbeing ,placed-in position-1, the` time-consuming sinceY the` operationbecomes specic adjustment made initially mustzbe Arepeated each timeAtheitocl is being repositionedfor dressing service, eachtruing-operation thusrepresenting a time :expenditure ofconsiderableextent and value' where dressingl is made frequently.v

The present invention` is designed to meet this Ycondition by providingavunit which, after ithas been once properly adjusted to providef theAdressing operation, can `be removed bodily'asa unit and-v replacedas-needed; since theadjustments are retained Whiletheunitis inactive-.itbecomes necessary only. to. replaceV the unit inl its positionforservice, and then providefthe; dressing foperation.- The unit is alsoadditional--A ly serviceable fordressing the sides'of'the grind-v ingwheel, thusenablingthe wheel dressing-to include sharpening. Theunit isof simple formation, sturdy in construction, simple as toadjustments,and of durability structurally.,

To these and otherends, the-naturev of whichwill be readily understoodas vthe-invention s-l` hereinafter disclosed, said invention consists inMachines.A of. this vtype are in.-

theimproved construction and combinationsof y parts hereinafterdescribed in detail, illustrated in the accompanying drawing, and moreparticularly pointed out in the appended claims.

In theaccompanying' drawing, in which similar reference charactersindicate similar parts in each of the views- Figure -lis a top plan viewof the unit of thev invention, certain parts of the grinding mae chinebeing shown by dotted lines, thus indicating the position ofthe unitduring service.

Figure 2 is a side elevation of the unit, with parts broken away, theview also showing machine parts in dotted lines.

Figure 3 is a view, partly in section and partly in elevation of oneform oi supporting structure which may be utilized, this supportingstructure serving as a part of the unit.

The grinding machine to be serviced isnot disclosed in complete detailherein, but parts thereof are shown by dotted lines. For instance,y

thegrinding wheel is shown at A, with a part of the bed shown aty B, thelatter being reciprocable across the face of the Wheel, as indicated bythe dove-tail guide b in Figure 2. The bed carries a headstock and atail stock-the centering points of these are indicated respectively at Cand -D-these, during normal grinding operations, supporting the workbeing ground and which is moved across the face of the grinding wheel byreciprocating bed movements While the wheel is being rotated. There area numbenof forms of machines of this type, but al1 of them' utilize theabove elements as apart of the equipment so that it is unnecessary toillustrate morethan as indicated', these parts having directrelation tothe unit operations.

The underlying fundamental of the present-inventionl is presentedby thefact-that the unit is so formed and arranged that it can be substi-`tuted for-the work in the work mounting, anclgbyl preventingv unitrotation While permitting all necessary adjustments, it is possible toproperly ad just the dressingtool lrelative-to the wheel, after.

which the unit can beremoved'from andreplaced in position with'the easeand simplicity of a removal and positioning of a succession'of` the Workpieces, the unit adjustments remaining. constant so that thereplacementrestores* the conditionsas'to angularity, etc., which' werevprovided during f the initial dressing-action, en.- su-ringguniformityin successive dressings.

Specifically, the -unit oriinstrumentality-is'con-' sifructed-oiy anumber of 'members ladapted to be "assembled and adjusted relative toeach other and to the machine. The main members are the carrier I9 forthe dressing tool, an L-shaped element II and a supporting member I2.Member I2 may be an elongated bar of uniform diameter having its endsrecessed to cooperate with the head and tail stock centering devices;however, it is preferred that this member be of the adjustable type,provided by two elongated elements I 2a of medium length, each elementbeing provided with the recessed end I2b to cooperate with the centeringpin, and the other end formed with an axial recess I2C which isthreaded, the threads being formed to receive a threaded connection I2dto permit adjustment in the length of the member; obviously, on theinitial positioning of the unit, either end element |20, of the assemblymay be rotated to rproduce a desired length of member for use with theparticular head and tail stock structures of the machine for which theunit is being prepared to provide the dressing operations. Member I2 ismounted in position on the head and tail stocks, after which carrier Iand element II are clamped to it, these structures being provided withopposing notched faces to engage member I2 and position the unit.

The dressing tool carrier I0 is in the form of a block, preferablytrapezoidal in form in side elevation and with the top and bottompreferably presenting the parallel sides, and with the bottom side ofgreater length from front to rear; this lower side carries the V-shapednotch Illa close to its front edge, this notch being designed to overliethe top of member I2. The block IU carries a pair of inclined openingswith the openings inclined downwardly from rear to front, theinclination being at a selected angle. These openings are arranged inspaced relation, with the axis of both openings lying on a plane angularto the top and bottom planes of the block. One of these openings I3, isdesigned to receive the dressing tool for the circular face of thegrinding wheel, the opening being internally threaded, while the tool I4therefor is of extended length and threaded externally, the tool havingat its rear end a knurled head Ma by means of which the tool can bereadily adjusted lengthwise of opening I3. The forward end of the toolis of the usual type, having a recessed threaded zone designed'toreceive the diamond-holding cup Mb, the diamond of which is to providethe dressing of the wheel face. The threaded zone of the tool'carries alock nut Mc cooperating with the rear face of the block to retain thetool in fixed position during'the dressing operation.

The second opening, indicated at I5, extends parallel with opening I3and is also screw-threaded. The opening is designed to receive thedressing tool (not shown) used for dressing the side faces of thegrinding wheel; tools for this purpose are well known and are ofdifferent types. The block carries a set screw I 5a designed tocooperate with such tool to retain it in its xed adjusted position.Since the dressing of the sides of the wheel is only an occasionalpossibility, the unit is designed more particularly for the dressing ofthe peripheral face, but is formed to permit of the side face dressingif the latter is required.

-Element II is a structure of general L-shape, being of a flatplate-like form one end zone of which is enlarged laterally to the widthof block I0, being narrowed in rear of that zone and bent downwardly ata suitable point, the latter being determined generally by theapproximate distance between the axis of member I2 to the rear face ofbed B. The upper face of element II is provided with a V-notch I Ia inits forward zone, complementally positioned relative to notch Illa, thewalls of the two notches permitting the block I0 and element II to belocated in contact with the positioned member I2 carried by the head andtail stock structures, the contact becoming a clamping contact by theuse of adjusting bolts I6, positioned at opposite sides of the assembly,and adjusting bolt or bolts I'I-the latter may be single (located midwayof the width of the assembly) or double (located at the sides), thelatter arrangement being indicated.

Bolts I6 have their stems threaded and extend through openings inelement II-but without a threaded engagement with such element-and arethreaded into a threaded opening I 0b formed in the block. Bolts I'I arelocated rearwardly of bolts l, and have their stems threaded anddesigned to pass through and threadedly engage the threaded walls ofopenings formed in element II, with the free ends of the stems designedto engage the under surface of block I0. The two sets of bolts thusserve to clamp the block I0 and element II to member I2 and at the sametime xedly anchor the lower face of the block and the upper face ofelement I I in spaced relation, with bolts I6 tending to draw the twotogether but only as permitted by the positions of the free ends ofbolts I'I.

The downwardly-extending leg IIb of member II is designed to overlie therear of bed B and especially the dove-tail portion thereof. Normally,the head and tail stocks carried by the bed extend upwardly to aposition where the work-carried by the head and tail stock centerisproperly located as to height relative to the grinding wheel; thisplaces the centers as materially above the top plane of the bed, thedistance being dependent upon the particular machine and the position ofthe grinding wheel axis. Hence, when locating member I2 in the positionof the work, the horizontal leg of element I I generally extendsrearwardly above the plane of the top of the bed. In practice the workaxis generally liespon a horizontal plane extending through the grindingwheel axis, and hence, the substituted member I2 will cause the upperface of the horizontal leg of element II as slightly below such axialplane; since the axis of the dressing tool is located above such axialplane, it is apparent that the pressures developed during dressing,especially those caused by the rotation of the grinding wheel, will tendto rock the unit 0n the axis of member I2 (the ends of which are carriedby the head and tail stock centers). To prevent this rocking movement,rthe leg IIb of element II preferably carries a pair of bolts I8 and I 9,the former being positioned above and juxtaposed to the top of thebed-preventing material downward swing of element II under suchpressures-while bolt I9 is positioned to extend below the lower edge ofthe dove-tail of the bed, preventing material rocking of member IIupwardlywith the free end of the bolt contacting the bed below suchdove-tail, the b olt carrying a lock-nut I9a for retaining the bolt inthe adjusted position; since bolt I9, due to its contact with the rearof the bed can also serve to prevent rocking of the unit downwardly, itis apparent that the unit will be protected against such rockingmovement even though bolty I8 be omitted-such omission is consideredwithin the purview of the invention; however, it is preferred to alsoemploy bolt I8 since it can serve to support the lengthyvhorzontal armof element II.

I Ib is preferably provided witha plurality of the threaded openingsIIcfor bolts I8 and Iii,Y thus enabling the latterto be secured in desiredpositions with different machines.

In providing the initial adjustments, theunit is accurately adjusted tothe particular machine, after which the dressing tool is advanced to thedesired point to provide the dressingY action on the peripheral face ofthe grinding wheel, and the bedvadvanced to carry the tool a-cross theface of the Wheel-if the wheel is movableinthe direction of its axis,the bed remains stationary; if the dressing requirements call for morethan one pass of the too-l, the latter is advanced for each additionalpass, nut |40 being manipulated each time. After the last pass, hasbeenmade, theunt is bodily removed from the machine by manipulating the headand move the centers from the ends of member i2, thus completelyfreeingthe unit from any positive connection with the machine. The unitis then placed aside in such condition, ready for repositioning when thesucceeding dressing is required, at which time it is brought to themachine, the ends of member I2 alined withthe head and tail stockcenters and the latter brought into position. It is then necessary onlyto adjust the tool to take care of any material decrease in dimensionsof the grinding wheel, and the dressing operation made active;obviously, this permits the successive dressings to take place undersimilar conditions as to dressing tool angularity, etc.

As will be understood, the bolts Hand I9- or bolt I9, if used aloneneednot have a cempletely accurate location relative to the edgesof thedove-tail; sincev the length of the horizontal leg of element il is manytimes that of the,

distance between the axis of member I2 anda vertical plane through theface of the dressing stone, it is apparent that material swinging of thedressing stone about the axis of member I2 can take place only by anextensive swing of the leg IIb in an arc about such axis, so that simplelooseness between the screw i9 and the lower edge of the dove-tail maybe present without providing any material swing of the dressing stone.Hence, the dressing operation is had under practically steadyconditions, .although the unit itself is so arranged as to permit itsbodily removal without disturbing any of the unit adjustments-removaland repositioning is provided with the simplicity of the removal of workfrom and the position ofv work relative to the grinding wheel.

While the above description presents the invention as applied togrinding machines wherein the work is moved relative to the grindingface in the direction of work axis, with the position of the grindingwheel remaining substantially constant, it is obvious that the inventionis equally applicable for use with machines in which the grinding Wheelis movable relative to the work additionally to the rotation of thewheel; for instance, the wheel support may be adjustable transverse ofthe bedthe wheel,vrather than the work being the movable element inbringing the work and wheel face into active relation; or, the work mayremain stationary in position, and the transverse and longitudinalmovements may be by the grinding wheel. These present various tailstocks to retypesf of the grinding wheel i structuresJ incom-'- mercialuse Vin addition to the formaabove discussed.

It is obvious, of course, that the ,inventioniisf applicable for usewitheach of the types, since member I2 takes the -position of the workinsuoli` machines, and the tool is supported by such. member. Hence,whether the bed is movable1tojward the wheel face, or vice versa, or thewheel. is shiftable axially rather than or additionally:

'to the bed, there is relative movement between 1 the bed, or the workthereon, and thegrinding; face, with the movement provided by one orboth of these parts, depending upon theV particular form of the machine.Since the tool is being sube stituted for the work in suchmachines, itisap,-v

parent that the'tool can be utilizedwith each; of the different typesand be operative in accord.` with the normal practice of the machineorfbyy such modications therein as may be found desirable.

As is apparent, the unit, structurally, isof -simple formation, sturdy,efficient inoperation, and@v carries the advantage -above pointed out.AndVl while I have shown a preferred arrangement of the unit, it willber readily understood that changes or modifications therein may befound desirable or essential in meetinggthe exigencies. of use or theindividual desires of the user, and I therefore reserve the right tomake any andall such changes or modifications as may be found necessaryor essential insofar as the same may, fall within the spirit and scopeofthe invention` as expressed in the accompanying claimawhen, broadlyconstrued.

I claim: f

1. In means for dressing grinding wheelsg` wherein the grinding machineis of thetype in i which the work is carried by a bed with the workcarried by head and tail stock centers and with., the machine operativeto provide relative movement between the work and grinding wheel in adirection parallel to the axis of the grindingz wheel, said dressingmeans comprising aunit Aor instrumentality formed to support thedressing tool, said unit or instrumentality including a membercooperative with the head and tail stock centers, a dressing toolsupport and an L-shaped element clamped to the member to therebydefinitely locate the unit relative to the grinding wheel peripheralface, said L-shaped element having one of its legs overlying the topplane of the bed and the other leg extending downwardly into overlyingrelation to the rear face of the b ed, said latter leg carrying anadjusting screw adapted to underlie the dove-tail of the bed and' tocontact the body of the bed below the dove-tail, whereby the unit willbe held against rotative movement on the axis provided by the mountingof the member on the head and tail stock centers, and whereby the unitis freely removable bodily by release of the member from the head andtail stock centers to thereby retain the initial adjustments of the unitand render the unit available for a succeeding dressing operation on thewheel by restoring the member to its position relative to the head andtail stock centers.

2. A unit as in claim 1 characterized in that the member is adjustableas to length.

3. A unit as in claim l characterized in that the member is formed o apair of elements each having an end recess cooperative with a stockcenter and a threaded axial recess leading inwardly from its oppositeend, the pair of elements being operatively connected in axial alinementby an interposed threaded element to permit adjustment in the length ofthe member.

4. A unit as in claim 1 characterized in that the dressing tool supportis in the form of a block of trapezoidal form in side elevation, withthe block having a threaded bore through which the dressing tool extendsand is adjustably mounted, said bore having its axis inclined downwardlyfrom rear to front of the block to thereby present the tool to the wheelperipheral face in direction approximating a radius of the Wheel.

5. A unit as in claim 1 characterized in that the dressing tool supportis in the form of a block of trapezoidal form in side elevation, withthe block having a threaded bore through which the dressing tool extendsand is adjustably mounted, said bore having its axis inclined downwardlyfrom rear to front of the block to thereby present the tool to the wheelperipheral face in direction approximating a radius of the wheel, theangle of inclination of the bore being approximately normal `to theangularity of the rear face of the block to the vertical to therebypermit the locknut of the dressing tool to lock the latter in itsadjusted position. i

6. A unit as in claim 1 characterized in that the dressing tool supportis in the form of a block of trapezoidal form in side elevation, withthe blocking having a threaded bore through which the dressing toolextends and is adjustably mounted, said bore having its axis inclineddownwardly from rear to front of the block to thereby present the toolto the wheel direction approximating a radius of the wheel, said blockcarrying a second threaded bore positioned to permit mounting of adressing tool for dressing the sides of the wheel.

'7. A unit as in claim 1 characterized in that the dressing tool supportis in the form of a block of trapezoidal form in side elevation, withthe block having a threaded bore through which the dressing tool extendsand is adjustably mounted, said bore having its axis inclined downwardlyperipheral face in from rear to front of the block to thereby presentthe tool to the wheel peripheral face in direction approximating aradius of the wheel, the forward zones of the lower face of the blockend of the upper face of the L-shaped element being notched to receivethe periphery of the center-supported member for the clamping operation.

8. A unit asin claim 1 characterized in that the dressing tool supportis in the form of a block of trapezoidal form in side elevation, withthe block having a threaded bore through which the dressing tool extendsand is adjustably mounted, said bore having its axis inclined downwardlyfrom rear to front of the block to thereby present the tool to the wheelperipheral face in direction approximating a radius of the wheel, theforward f zones of the lower face of the block and of the upper face ofthe L-shaped element being notched to receive the periphery of thecenter-supported member for the clamping operation, the block andelement assembly including a screw for directly connecting them in theclamped position and a screw for adjustably ments of the block towardthe element.

9. A unit as in claim 1 characterized in that the downwardly-extendingleg of the element additionally carries an adjusting screw adapted tooverlie the top of the bed in the zone of the dove-tail, said screwtogether with the rst screw presenting abutments cooperative with thedovetail for preventing rotative movements of the unit about the axis ofthe member.

10. A unit as in claim 1 characterized in that, the downwardly-extendingleg of the element.

additionally carries an adjusting screw adapted to overlie the top ofthe bed in the zone of the dove-tail, said screw together with the rstscrew presenting abutments cooperative with the dovetail for preventingrotative movements of the unit about the axis of the member, said legbeing provided with a plurality of spaced openings to permit variedpositioning of the adjusting screws to compensate for machinecharacteristics.

GEORGE D. SCHOGER.

limiting the move-

